"In the Gospels themselves when they describe this meal, they only describe bread and wine as being present," Craig Wansink ... So, it was up to the individual artists to decide what else might have been served, and sizes.

The paintings were analyzed with a computer program that scanned the depicted food items and calculated their dimensions. To account for varying sizes of the paintings and their foods , the size of bread loaves and main dishes was indexed based on the average head size of the people around the table -- or what the researchers call the "Bread-to-Head" ratio (and, of course, the "Main-Dish-by-head" ratio, too).

"The last thousand years have witnessed dramatic increases in the production, availability, safety, abundance and affordability of food," said Brian Wansink, "We think that as art imitates life, these changes have been reflected in paintings of history's most famous dinner."